A large number of devices are arranged in as limited space of a driver's cab of a railcar. For example, in the case of the driver's cab including a passage located at as middle portion thereof, the devices are arranged at not only a driver's platform provided at a front side of one of both railcar-width-direction sides sandwiching the passage and a driver's platform provided at a front side of the other railcar-width-direction side but also a wall surface and ceiling of a driver's seat side. Further, some of the devices are connected to one another by electric wires for signal transmission and reception. Connecting work for coupling the devices to each other is conventionally performed by a procedure including the steps of: laying the wires behind the wall surface of the driver's cab; attaching the devices to the drivers cab; and connecting the wires to the devices. However, since these steps cannot be performed concurrently, this procedure extremely takes time, and this has been cause to delay manufacturing steps of an entire manufacturing line.
When manufacturing railcars, a construction method that is called a unit construction method (module construction method) is adopted in some cases. According to this unit construction method, a part of the railcar is manufactured as a unit (module) at a place outside the railcar, and then the unit is carried in the railcar and attached to at pre-determined position. There are PTL1 and PTL 2 as literatures related to the unit construction method. Each of PTL 1 and PTL 2 discloses a railcar manufacturing method of carrying a unitized rig (equipment) in the railcar and attaching the unitized rig to the railcar. According to each of PTL1 and PTL2, this method can improve the work efficiency. However, PTL1 and PTL2 do not describe the unit construction method for the driver's cab.